Two Senate Democrats want the public to know more about the rules behind the targeted killing of American citizens using drones.

"I believe every American has the right to know when their government believes it is allowed to kill them, and the public release of this memo is a positive step toward reducing the secrecy that surrounds this question," Sen. Ron Wyden said in a statement. "However, there are many important questions that this memo does not address."

Wyden, a Democrat from Oregon who serves on the Intelligence Committee, was responding to the disclosure of a redacted form of a controversial 2010 Justice Department memo authorizing a lethal drone strike against Anwar al-Awlaki. The memorandum from the Office of Legal Counsel was released under court order from the New York-based Second Circuit.

"It is my hope that making this memo public will generate new pressure for the executive branch to answer other pressing questions," Wyden added. "For example, how much evidence does the president need to determine that a particular American is a legitimate target for military action? Or, can the president strike an American anywhere in the world? What does it mean to say that capturing an American must be 'infeasible'? And exactly what other limits and boundaries apply to this authority?"

The release came about after the Obama administration agreed to accept the order for the memo to be made public as part of the negotiations that led to confirmation of David J. Barron to be a federal appeals court judge on the First Circuit.

As an acting assistant attorney general, Barron authored the memo released Monday. Sen. Mark Udall, D-Colo., backed Barron only after administration assurances about the memo.

In his own statement on Monday, Udall pointed to other questions that haven't been answered about the drone policy.

"The federal appeals court's release of the Justice Department's legal justification for the targeted killing of Americans is a victory for government transparency and the type of strong, public oversight of intelligence agencies I have long championed," Udall said. "But I also have called for — and not received — answers to questions such as how much evidence the government requires in order to make an American a legitimate target, how an 'imminent' threat is defined, and what are the geographical boundaries of these authorities, among others. I will continue to press for these answers and for more information to be made public on additional legal opinions regarding targeted killings."